Advertisements
Advertisements
प्रश्न
Answer the following question.
State Gauss's law for magnetism. Explain its significance.
Advertisements
उत्तर
The net magnetic flux (ΦB) through any closed surface is always zero.
This law suggests that the number of magnetic field lines leaving any closed surface is always equal to the number of magnetic field lines entering it.
Suppose a closed surface S is held in a uniform magnetic field `vecB`.
Consider a small vector area element Δ`vec"S"` of this surface.
Magnetic flux through this area element is defined as ΔΦB = `vec"B".Δvec"S" `
Considering all small area elements of the surface, we obtain net magnetic flux through the surface as:
ØB = `sum_"All" ΔØ_"B" = sum_"All" vec"B". Δvec"S" = 0`
APPEARS IN
संबंधित प्रश्न
A charge ‘q’ is placed at the centre of a cube of side l. What is the electric flux passing through each face of the cube?
Draw a graph of electric field E(r) with distance r from the centre of the shell for 0 ≤ r ≤ ∞.
State Gauss's law in electrostatics. Show, with the help of a suitable example along with the figure, that the outward flux due to a point charge 'q'. in vacuum within a closed surface, is independent of its size or shape and is given by `q/ε_0`
q1, q2, q3 and q4 are point charges located at points as shown in the figure and S is a spherical gaussian surface of radius R. Which of the following is true according to the Gauss' law?
Which of the following statements is not true about Gauss’s law?
Refer to the arrangement of charges in figure and a Gaussian surface of radius R with Q at the centre. Then
- total flux through the surface of the sphere is `(-Q)/ε_0`.
- field on the surface of the sphere is `(-Q)/(4 piε_0 R^2)`.
- flux through the surface of sphere due to 5Q is zero.
- field on the surface of sphere due to –2Q is same everywhere.
An arbitrary surface encloses a dipole. What is the electric flux through this surface?
In 1959 Lyttleton and Bondi suggested that the expansion of the Universe could be explained if matter carried a net charge. Suppose that the Universe is made up of hydrogen atoms with a number density N, which is maintained a constant. Let the charge on the proton be: ep = – (1 + y)e where e is the electronic charge.
- Find the critical value of y such that expansion may start.
- Show that the velocity of expansion is proportional to the distance from the centre.
The region between two concentric spheres of radii a < b contain volume charge density ρ(r) = `"c"/"r"`, where c is constant and r is radial- distanct from centre no figure needed. A point charge q is placed at the origin, r = 0. Value of c is in such a way for which the electric field in the region between the spheres is constant (i.e. independent of r). Find the value of c:
